Fuel control device



Feb. 17, 1942. F A, KOMMER ET AL 2,273,205

FUEL CONTROL DEVI CE FledJan. 26, 1940 u vSheets-Sheet l ATTORNEY 5Sheets-Sheet 2 F. A. KOMMER ET AL FUEL CONTROL DEVICE Filed Jan. 26,1940 Feb. 11, 1942.

Feb- 17, 1942. F. A. KOMMER ET Al.

FUEL CONTROL DEVICE Filed Jan, 2e, 1940 3 sheets-sheet s INVENTOPS FREDA. KoMML-R mw. l.Y Mu Sw Rw U. T xm S ma Patented Feb. 17, 1942 FUELCONTROL DEVICE Fred A. Kommer and Russell F. Smith, St. Louis,

Mo., assignors to Carter Carburetor Corporation, St. Louis, Mo., acorporation of Delaware Application January 26, 1940, Serial No. 315,724

' (ci. 1st-cs) Claims.

This invention relates to fuel supply devices for oil burners and thelike and more particularly to the provision of a combination constantlevel chamber, fuel metering control, and safety device.

In oil burner installations of the gravity feed type, there iscustomarily provided an elevated fuel storage tank and a vented constantlevel chamber in which the fuel is maintained normally at a levelslightly above the high nre level in the burner. The oil is fed bygravity to the burner through a suitable metering orifice, manually orautomatically controlled. A safety device is also desirable to shut offthe fuel supply to the constant level'chamber in the event of faultyfunctioning of the oat valve mechanism, whether due to failure of theneedle valve to seat properly or damage to the oat.

Combination constant level chamber and safety devices as heretoforedevised have been complicated and expensive so that their use,particularly with small, domestic heating plants, has been limited.

An object of the present invention is to provide a device of the abovecharacter that is simple, compact, positive in operation and economicalto manufacture.

Another object is to provide safety cut-off mechanism for a fuel supplydevice having easily accessible means for manually tripping the cutoffvalve.

Another object is to provide a novel, adjustable fioat valve mechanismfor controlling the constant fuel level.

Another object is to provide a simple, effective drain valve for theover-ow chamber.

Another object is to provide a novel filtering screen arrangement whichmay be removed as a unit Without affecting other parts of the device andwhich is self-cleaning during disassembly thereof.

The invention resides in the improved construction and combination ofparts hereafter described and illustrated in the accompanying drawingsin which:

Fig. 1 is a vertical longitudinal section through the device and takensubstantially on line I-I of Fig. l2.

Fig. 2 is a vertical transverse section taken substantially on line 2-2of Fig. 12.

Fig. 3 is a partial vertical transverse section- `taken substantially online 3-3 of Fig` l2.

Fig. 4 is a detail section taken on line 4--4 of Fig. 12.

Fig. 5 is a perspective view of the safety plunger. v

Fig. 6 is a partial section illustrating the trip mechanism in thecocked or open position.

Figs. 7, 8 and 9 are enlarged detail sections illustrating,respectively, the closed, low fire or 'in a casing I, convenientlyformed integrally, in-

cluding upstanding side walls 2 andcurved end walls 3 and 3a, and abottom wall or floor 4 having a hollow, cylindrical structure 5extending longitudinally on the lower surface thereof'and receiving theelongated strainer unit indicated generally at 6. A transverse partition'I divides the casing into a main fuel reservoir and an over-flowchamber. A tapped inlet opening 8 is provided at one end of cylindricalstructure 5 for attachment of a fuel line connecting the device to aremote fuel tank (not shown). An orice 9 in the upper wall ofcylindrical structure 5 opposite inlet 8 forms a communication betweenthe fuel inlet and the interior of the casing and also forms a seat forsafety needle valve I 0, reciprocable in an apertured boss II projectingupwardly from the casing floor. A lateral passage I2 connects theinterior of boss II with a second apertured boss I3 threadedly mountinga valve seat member I4, having axial and radial passagesll4a and I4bcontrolled by a needle valve I5. Valve I5 has a universal ballattachment, as at I6, to a screw I'I threaded in an inverted U- shapedarm I8 projecting from main fioat I9.`

A pin 20, extending between the depending legs of float arm I8, isseated in a groove 2i in the upper surface of a stanchion 22 projectingfrom the casing floor adjacent boss I3 and is secured in position by theoverlapping head of a screw 23 threaded into the stanchion. By means ofthis arrangement, the main float and needle valve assembly may bereadily removed for inspection or repair after screw 23 is withdrawnthrough an opening 24 in the float arm. The position of main needlevalve I5 relative to float arm I8 may be adjusted by means of screw I1,

a coiled spring 25 being interposed between the screw head and float armfor stability. The universal or swinging mounting of needle valve I5facilitates proper seating and movement of the valve in its guidesirrespective of the positions of cat `I9 and screw I1 and even thoughthe valve, seat, and guides may be worn.

Safety valve IIJ is constantly urged upwardly and away from its seat 30in orifice 9 by means of a coiled spring 3| interposed between the lowerinterior wall of apertured boss II and a collar 32 rigid with the valveand slidably tting the inner wall of the boss. Anactuator stem 33projects upwardly from valve I through a closely tting hole 34a inthreaded plug 34 closing the top of boss I I. Collar 32 seats againstplug 34 when valve I0 is open and insures sealing of the stem openingtherein. A plunger 36 is slidably received in a depending boss 31 on thecover member 38 of the casing and, at its lower extremity, has a disc 39formed rigidly therewith and presenting a lower, axially facing surfaceor shoulder 39a. Plunger 36 is constantly urged downwardly by means of acoiled spring 40 interposed between the disc and cover 38 andsubstantially stronger than spring 3|. A knurled handle 4I is providedat the upper extremity of plunger 36 and easily accessible from outsidethe reservoir.

A pin 42 carried by a pair of lugs 43 depending from cover 38 pivotallysupports a long arm 44 extending over partition 1 and carrying safetyfloat 45 at its outer extremity. A detent or latch 46 is formed on thepivoted end of arm 44 and disposed to latchingly underlie and engagedisc 39 to maintain the same in its elevated position, shown in dottedlines in Fig. 1 and also shown in Fig. 6. Disc 39 has a chamfered upperedge 48 and a cut-away segment 31 forming an eccentric recess in itsperiphery to provide for releasing the safety trip mechanism by manuallyrotating plunger 36 about its longitudinal axis.

The operation of the safety trip mechanism isv as follows: n

To open the safety valve I0 and cock the trip mechanism, plunger 36 ismanually lifted to the position shown in Fig. 6 which comprises spring40 and causes detent 46 to ride past the chamfered edge 48 of disc 39and latch against the lower surface thereof. Assuming that the device isproperly attached to an elevated fuel tank, fuel will be admitted to theportion of the casing on the left side of partition 1, forming the mainfuel reservoir, to a predetermined level :zr-x, whereupon main float I9will close inlet valve I5. The position of the float with the valveclosed, and consequently thelevel :rmay be adjusted by means of screw I1which may be readily reached with a screw driver when the reservoircover is removed. Thereafter, if for any reason, such as improperseating of needle valve I or puncturing of float I9, an excessivequantity of fuel should be admitted to the casing, which has y theeffect of excessively increasing the delivery pressure at the outletport, the fuel will be spilled over partition 1 into the safety chamberat the right side thereof, raising safety fioat and ultimately releasingdisc 39 from detent 46 so as to permit` plunger 36 to be snappeddownwardly by spring 46, striking valve actuator`33 and clos- A ingvalve I6 against its seat 30 with considerable The safety float andactuating plunger may sleeve valve.

be readily removed as a unit with the bowl cover to permit inspectionand repair and, after reassembly, the safety valve may be re-latched inits open position as above described. In some cases it may be desirableto manually close the safety valve, as when the apparatus is to remainout of operation for a substantial time, and this may be accomplished bymerely rotating plunger 36 so as to bring cut-away segment 41 on disc 39into registry with safety float arm detent 46.

The Fig. 4 shows a simple valve arrangement for draining the safetyfloat chamber. This includes an apertured boss or cup member projectingoutwardly from casing side wall 2 at the lower edge thereof andtelescopingly receiving a second cup member 5I. A stem 52 projectsaxially from the member 5I through boss 59 and orifice 53 in the casingwall and, at its inner extremity, is provided with a conical valve head54 shaped to seat against the edge of the orifice. Valve 54 is normallyheld in its closed position by means of a coiled spring 55 compressedbetween cap 5I and the casing wall around orifice 53. To open the valve,it is merely necessary to press inwardly on member 5I, permitting egressof accumulated fuel through port 53 and slot 56 in the lower wall boss50.

The fuel metering arrangement, as shown in Figs. 2 and 3, will now bedescribed. Depending from rthe bottom wall of the casing on each side ofcylindrical structure 5 are the apertured bosses and 6I and alignedtherewith are a pair of apertured bosses 62 and 63 extending upwardlyinto the casing. The -bosses 60 and 62 are provided with connectingorifices 64 and 65 for conducting liquid fuel from the constant levelchamber to the burner by means of a suitable pipe (not shown). In thepresent instance, the device is intended for use with a single burneronly and, accordingly, the other outlet is closed, as at 66, the castingbeing formed with the extra bosses 6I and 63 so that the device may beeasily modilied so as to control the fuel supply to a pair of burners,if desired.

Tightly seated in the upper portion of orifice 65 is the lower extremityof a vertical tube 61 having a key-shaped port 68 located slightly abovethe surrounding shoulder formed by boss 62. Slidable on tube 61 is asleeve valve 69 having lateral venting ports 10 above the fuel level andconnected at its upper extremity by means of a pin 1I to a knurled nutmember 12 having a cup-shaped portion 13 slidable in an apertured boss14 projecting upwardly from the casingcover 38. A small sheet strip 15ts tightly on casing wall and port 69a at the upper end of sleeve 69 toprevent rotation of the sleeve and pin 1I rigid therewith when cap nut12 is rotated for manually adjusting the setting of the A coiled spring16 is seated between strip 15 and cup 13.

'I'his form of metering valve is particularly advantageous forseparately formed accurate, in-

expensive production in that the outer surface of tube 61, after hole 69is punched, may be centerless ground to eliminate burrs caused bypunching and to provide a smooth bearing surface perfectly fitting theinner surface of sliding sleeve 69. Sleeve 69 may be accurately formedby automatic screw machine operations. Thus, no hand operations arenecessary as would be required, for instance, if the metering port orports were placed in the movable sleeve arranged to. telescope into astationary boss or tube communicating with the outlet passage.

Secured to cover 38 by means of a screw 80 and nut 8| is a bi-metalthermostatic strip 82 (Fig. 2) With its free outer extremity recessed toembrace the circumferentially indented portion 83 of nut 12. A metalbracket 84 extends between the bends of thermostat 82 and mounts anelectrical resistance coil 85 which may be energized thermostaticallyfrom a remote point, by means of wiring 86 (Fig. 10) to heat bi-metalstrip 82 causing upward bowing of the free end thereof and. raising ofnut 12 and sleeve valve 69.

In order to limit the extreme positions of the slide valve, a kerfeclscrew 81, threaded in a depending post 88 on the casing cover (Fig. 3),has a tapered extremity 89 inserted into an annular recess 19 formed inthe outer wall of the sleeve. The sides of the groove are beveled at thesame angle as the tapered extremity of the screw. The high position ofthe slide valve. and consequently the maximum fuel supply (Fig. 9), islimited by engagement of screw 81 with the lower edge of recess 19 inthe valve Where the lowering of the valve is to be limited to pilot orlow fire requirements (see Fig. 8) this may be accomplished byengagement of the screw with the upper edge of Irecess 19. It isfrequently desirable to completely close the outlet valve, this ,may beprovided for by properly regulating the sizes of screw tip 89 and recess19, or by permitting the sleeve valve to engage boss 62 at th: lowerextremity of its movement.

Vents 10 communicating with the interior of tube 61 provide for theescape of gases which z may form in the fuel line posterior to themetering orifice 68.

Figs. l0, 11 and 12 show the sleeve valve arrangement of Figs. 2 and 3,respectively, in the fully closed, low fire or pilot, and high firepositions. The shape `of port 68 is such that in the low re position,Fig. 11, wherein the port meters the fuel at a very slow rate, theeffective port opening approaches circular shape. This is particularlyadvantageous in that there is no relatively narrow portion of the port,such as is the case where' the fuel is metered through a triangular portor through the annulus around a needle valve inserted into or throughthe. port. Thus the possibility of dirt and gaseous bubbles blocking theport is reduced to a minimum.

Obviously the metering port may be shaped cup 91 is snugly seated on theinner portion of nipple 95 and held in position against a shoulder 98 ontube 90 by a spring key or Wire 99, conveniently of hair-pin shape anddetachably applied to annular groove in the outer wall of the nipple. Acylindrical screen |l3| of suitable fine mesh material, is secured atone end to cup 91 and at the other end snugly ts the shoulder portion|02 adjacent threaded head 91| of the tube member. i

The described strainer structure may be readily assembled with anddis-assembled from the remainder of the constant level and safety devicewithout affecting any other part thereof. The relatively large area ofscreen is firmly supported throughout its length by cup 96, ribs 93, andshoulder |02 and the entire unit is also firmly supported at each end incylindrical structure so as to prevent leakage. The close t betweennipple 95 and shoulder 96 is such that foreign, solid particles areprevented from passing through theseparts. A11 such foreign materialwill be retained inside screen |0| and, when the unit is withdrawn fromits mounting, the screen may be disassembled for cleaning by removingkey 99. Cup 96 is then slid oi nipple 91drawing the screen across ribs93 thus scraping off or loosening foreign material adhering to the innersurface of the screen.

The device described functions effectively to meter fuel supplied to theburner and also to prevent over-flow from the constant level chamberwith consequent nre hazard in case of faulty operation of the needlevalve mechanism. The device is simpler than other somewhat similardevices with which I am familiar and embodies features facilitatingproduction as wellas the inspection and repair thereof after a serviceinstallation. The invention is not limited to the strlfcture shown butmay be modified in various respects as will occur to those skilled inthe art. The exclusive use of all modifications as come within the scopeof the appended claims is conas desired to obtain the proper metering offuel under various burner conditions.

'In the modification in Figs. 13 and 14, both r the tube 61a and sleevevalve 69a provided with metering ports 68a and 6817 which varinglyregister so as to provide for different sizes of effective meteringorifice according to the position of the sleeve valve. Fig. showsvertically spaced ports 68e and 68d, the former serving to supply fuelfor the low fire or pilot fiame while both ports supply fuel for highfire requirements.

The strainer unit, (Fig. 1) previously referred to by the referencecharacter 6, comprises an elongated tube having a central. longitudinalbore 9|, a series of outlet ports 92,and radial ribs or shoulders '93.The left hand end of the tube is closed and provided with a threadedhead 94 for screwing the unit into the open end of cylindrical structure5 on the bottom of the casing. The opposite end of the tube is open andprovided with a nipple 95 which snugly fits into a collar 96 in the wallof inlet port 8. A

templated.

We claim:

1. In a liquid supply system, a liquid passage having a valve seat, avalve controlling said seat, means normally urging said valve toward itsopen position, a valve actuating plunger for said valve and having anaxially facing shoulder, means yieldingly urging said plunger towardsaid valve, latch means constructed and arranged to engage said shoulderand hold said plunger in a cocked position, and a device responsive topredetermined liquid pressure conditions in said system to release saidlatch and permit said plunger to close said valve, said plunger beingmanually rotatable about its longitudinal axis to disengage said latchmeans from said shoulder and trip said actuating plunger.

2. In a liquid supply system, a liquid passage, a valve controlling saidpassage, and valve actuating mechanism therefor including means normallymaintaining said valve in its open position, a valve actuating plungerdevice havingan axially facing shoulder, a latch engageable with saidshoulder to hold said plunger device in an inactive position, and meansresponsive to pref determined liquid level conditions in said system totrip said latch and permit said plunger to move said valve to its closedposition, said plunger device being manuallyrotatable about itslongitudinal axis to release said shoulder from said latch and trip saiddevice.

3. In a liquid fuel control device, a liquid fuel reservoir having inletand outlet openings, means for maintaining the fuel supply to saidoutlet opening at a substantially constant pressure, a normally open,longitudinally movable safety cut-off valve in said inlet passage, avalve actuating plunger having a radially projecting shoulder, a latchengageable with said shoulder to hold said actuator in an inactiveposition, and means responsive to abnormal fuel pressure conditions insaid reservoir and outlet opening to trip said actuator and close saidvalve, said actuator being manually rotatable about its longitudinalaxis to disengage said shoulder from said latch and release said plungerto close said valve.

4. A liquid fuel control device as described in claim 3 in whichl saidradial shoulder is formed by a disc projecting from'said plunger andhaving an eccentric recess permitting manual tripping of said cut offvalve by rotation of said plunger.

A 5. In a liquid fuel control device, a constant level reservoir, inletand outlet passages communicating with said reservoir, a. chamber forreceiving overflow from said reservoir, a safety cut-oi valve in saidinlet passage, an actuating plunger for said valve and having an axiallyfacing, non-circular surface, a latch engageable with said surface forholding said plunger in a cocked position, and means responsive to apredetermined level of fuel in said overflow chamber to trip saidplunger'and close said valve, said plunger having a readily accessiblehandle and being rotatable thereby about its longitudinal axis torelease said latch from said surface and trip said plunger.

FRED A. KOMMER. RUSSELL F. SMITH.

